Unit 1: Control of the cell cycle

Question 1

What is a checkpoint

Answer 1

Mechanisms within the cell that assess the condition of the cell during the cell cycle and halt progression to the next phase until certain requirements are met.

Question 2

What does the protein cyclin combine with?

Answer 2

• combine with and activate cyclin-dependent kinases (CDK)

Question 3

What is the role of active cyclin-CDK complexes?

Answer 3

Phosphorylate proteins that regulate progression through the cycle. If sufficient phosphorylation is reached, progression occurs.